Re: Failing test case 67 Fatal errors but M4 continues producing output

[Bruno Haible]

Hi Joel,

> In the create_pipe_bidi invocation above, I set the slave_process argument 
> to true.  create_pipe_bidi passes that argument to create_pipe, which then 
> invokes register_slave_subprocess, which uses atexit to register a 
> function that invokes kill.
> 
> Moreover the documentation in pipe.h, which contains create_pipe_bidi, 
> says:
> 
>   If slave_process is true, the child process will be terminated when
>   its creator receives a catchable fatal signal or exits normally.  If
>   slave_process is false, the child process will continue running in
>   this case, until it is lucky enough to attempt to communicate with
>   its creator and thus get a SIGPIPE signal.

Oops, you're right. I had forgotten about this feature.

> I figured that killing it wasn't working properly on the reported platform.

Indeed.

The code in bison-2.4.2/src/output.c looks fine.

Can you help reproducing or debugging it, with just 2 executables: bison
and m4? (I.e. give a "how to reproduce" that does not involve bison's
testsuite? I'm not inclined to look into a 3 MB large machine generated
shell script.)

Bruno